help with front end and scopes

[Andre Groenewald <adres dot is dot gevat at gmail dot com>]

I am a bit stuck on global, file and local name spaces and scopes.

Normally my expression bindings is associated with a function, which
makes the function the scope of all the variables.

my front end can parse something like this:

int testfunc(int parmVar)
{
  int testfuncVar;
}

int testfunc2(int funcVar)
{
  int testfuncVar2;
}

Every function is individually gimplified and added and finalized.
Everything is chained and bind correctly.

parser->Fndecl = build_fn_decl(functionName, fnDeclType);
....
gimplify_function_tree(parser->Fndecl);
cgraph_node::finalize_function(parser->Fndecl, true);

I want to expand my front end to something like this:

module TestModule
{
  int moduleVariable;
  class TestClass
  {
    int classVariable;
    int testfunc(int parmVar)
    {
      int testfuncVar;
    }
  }
}

The question is what should TestModule be declared as, what tree type
or declaration function, and also TestClass. How should TestModule be
gimplified and then finalized.

Thank you
André